In recent semiconductor devices including a power semiconductor element or a semiconductor laser element, a larger electric current flows through the semiconductor element, and the amount of heat generated from the semiconductor element is increased accordingly. For example, in a high-power semiconductor laser device used for laser processing, a larger electric current flows through a semiconductor laser element mounted on the device in order to obtain a high-power laser beam, and the amount of heat generated from the semiconductor laser element is increased accordingly. When reaching a high temperature, semiconductor laser elements suffer performance degradation, such as a decrease in laser output. To stabilize the performance of semiconductor laser elements and prevent the overheating thereof, semiconductor laser devices are configured to have a cooling function of releasing heat from both sides of the semiconductor laser elements.
With reference to FIG. 18, conventional semiconductor laser device 900 in Patent Literature 1 will be described. FIG. 18 is a perspective view and a side view of conventional semiconductor laser device 900.
As illustrated in FIG. 18, conventional semiconductor laser device 900 is provided with submount 902 and LD (Laser Diode) bar 903 on an end portion of heat sink 901. Insulating layer 904 is provided in a region which is on heat sink 901 and in which submount 902 is not provided. Bumps 905 are formed on LD bar 903, and lead-out electrode 906 is provided on insulating layer 904 and bumps 905. Furthermore, filler 907 is filled in a space between LD bar 903 and lead-out electrode 906 in which no bump 905 is present.